Of the more than 6 billion people in the world, more than half live in rural areas and more than 40% are involved in the production of food and fiber. But, as would be expected, there are substantial differences between the developed and developing worlds in how much human effort it takes to supply the food and fiber needs of their populations. In the developed world, only 7% of the population is involved in agriculture, while in the developing world just over half spend their working lives in farming activities. The importance of an adequate supply of food cannot be overemphasized. Adequate fuel for mental and physical activity is necessary for life and health. In addition, the value of food and fiber to the world economy is not trivial. The worldwide gross domestic product (GDP), the total value of goods and services produced, is approximately $7600 per capita or $46 trillion; agriculture accounts for 6.2% of the GDP or nearly $3 trillion. The world system of production, processing, distribution, and marketing is incredibly complex. We will review the highlights of that system here (1).